In the photo I uploaded is the beginning of a study of inductors in circuits. They explain there why Ec must have the same value as En, but I don't get it: If the total electric field inside the conductor is 0, then there should be no current in the conductor (because there is nothing which moves the charges). But the resistance is negligible (very close to 0), so the current should have an enormous value (because outside the coil we hare the generator that provides a emf). And also if the current inside the coil is 0, how is possible to have an induced emf. Can someone explain what is wrong in my thinking (because I doubt that the book is wrong) and eventually explain this thing better?